The present invention is directed to improvements over my earlier U.S. Pat. Nos. 4,285,516, 4,530,498, 4,700,947, 5,320,593, and 5,391,134, each entitled "AMUSEMENT AND/OR EXERCISING DEVICE." The present invention is an exercise or amusement device having an improved centering mechanism which improves upon the devices disclosed in my earlier patents, making it easier for a user to learn to use the device and making it safer for all users.